STM32 the difference between the Gpio push-pull output and the open-drain output

First look at the following schematic diagram of the STM32 Gpio as follows:

When the port is configured for output:

Open-Drain mode: output 0 o'clock, N-mos conduction, P-mos not activated, output 0.

Output 1 o'clock, N-mos high resistance, p-mos not activated, Output 1 (requires external pull-up circuit); This mode allows the port to be used as a bidirectional IO.

Push-Pull mode: output 0 o'clock, N-mos conduction, P-mos high resistance, output 0.

Output 1 o'clock, N-mos high resistance, P-mos conduction, Output 1 (no external pull-up circuit required)